1. Field of the Invention
The present invention is directed to a storage vessel for explosives, and more particularly, to a containment vessel for storage of explosives in areas where personnel and/or inhabited buildings are present at close standoffs.
2. Description of Related Art
Explosion containment vessels are known in the art. Typical vessels are large rectangular units having an external shell and a series of reinforcements and shock absorbing material between the shells.
U.S. Pat. Nos. 6,173,662 B1; 5,884,569; and Re. 36,912 to Donovan teach an apparatus for controlling and suppressing explosions from explosive destruction of munitions by detonation in an explosion chamber, and explosion-hardening of steel work pieces. The apparatus includes a double-walled steel explosion chamber (i.e., has inner and outer casings). Ribs (I-beams) are spaced apart in the cavities between the chamber walls, ceiling, and floor for reinforcement. A fillet piece is welded in each corner to break the corner into two 45xc2x0 angles.
Before use, shock-damping sand is introduced into the fillable cavities. After use, the sand is removed to lighten the chamber for transport. The floor of the chamber is covered with shock-damping pea gravel. Vaporizable plastic bags of water are disposed about the munitions and/or the chamber to further absorb energy. Vent pipes penetrate the chamber and vent explosion products into manifolds leading to a tank or scrubber. When the chamber is used to dispose of munitions, an open-topped steel fragmentation containment unit is placed within the apparatus under a steel blast mast secured to the chamber roof.
These chambers have internal dimensions that allow an operator to enter, stand up, and work easily and have a length that permits long pre-welded sections of railroad trackwork to be inserted and explosion-hardened. The chamber is anchored to a concrete foundation. Some embodiments of the chamber are mobile.
U.S. Pat. No. 5,251,473 teaches an above-ground storage tank for flammable liquids. The tank includes inner and outer welded steel tanks. A space between the tanks is filled with granular insulating material, such as perlite, to prevent excessive heating of the fuel in the inner tank. The inner tank is partitioned defining a separate overfill containment space.
A current cylindrical explosives storage vessel that can contain an accidental explosion is made by Golan and has a U.S. Department of Defense standoff rating of 30 feet. However, the door system of this apparatus permits an excessive amount of venting through the door system, resulting in possible injury to personnel standing outside of the door.
Therefore, a need exists for an explosives storage vessel that can contain an explosion, accidental or intentional, which reduces the safe standoff to a minimum distance by permitting a minimum of venting through the door system, venting being in the form of damaging overpressure and/or extreme heat and flames.
It is an object of this invention to provide an explosives storage and accidental explosion containment vessel that is rated for a design charge weight of 10 kg (22lbs) of TNT at less than 20 feet.
It is a further object of this invention to provide a vessel capable of containing an explosion within the interior of the vessel and with minimal fragment mitigation.
It is a further object of this invention to provide an explosion containment vessel that is re-usable.
The present invention is a vessel for storing explosives and containing an explosion, accidental or intentional, which includes a container having a top and a bottom attached to a side wall. Preferably, the container is generally cylindrically-shaped, and the top and the bottom are elliptically-shaped. The top preferably includes at least one vent through which products of an explosion are exhausted. Lifts may be provided on the top of the container for lifting and transporting the vessel. A door and closing system provides access to an interior of the vessel and mitigates the hazard from an explosion, resulting in a low safe standoff distance for the vessel.
Explosives may be stored in the vessel or may be detonated within the vessel without adverse affect to the environment surrounding the vessel. The vessel is rated for minimal fragment mitigation during an explosion and is capable of resisting multiple detonations of the design charge weight inside the vessel with little or no reconditioning required between explosions.
Another embodiment of the vessel further includes a liner positioned within the container, thereby defining a gap between the liner and the container. A fragment arresting lining (i.e., sand) fills the gap. After an explosion, the liner and fragment arresting lining are compromised. Therefore, the vessel in such an embodiment is not considered reusable without significant work to restore the vessel to its original condition. Yet another embodiment of the vessel includes a layer of insulation positioned between the container and the fragment arresting lining.